Comprehensive numerical investigations on the thermal performance of heat recirculating micro combustor with pin fins for micro-thermal voltaic system applications

Aiming at improving the relatively low energy output and energy conversion efficiency of the micro-thermal voltaic (MTPV) system, an innovative heat recirculating micro combustor with pin fins is designed. The effects of pin fins arrangement, hydrogen/air equivalent ratio on the energy output and performance of CHMC, HMCP and HMCI are compared and investigated. The result shows that when the V_in is 6 m/s and Φ is 1.0, the emitter power of CHMC is 72.76W, and that of HCMP and HCMI micro combustor are 75.99W and 76.35W. and the emitter efficiency of CHMC, HCMP and HCMI is 41.93%, 43.26% and 44.01%. HMCI has better energy output capability compared with CHMC and HMCP. Even though, HMCI brings a higher pressure drop, it is within the acceptable range. When the V_in is 6 m/s, the pressure drop from the pin fins only accounts for 26.4% of the total pressure drop for HMCI. Through the study of equivalent ratio, it is found that HMCI has good adaptability in different equivalent ratio range. This work provides new ideas for the development of MTPV system in the future.     

High voltage and self-healing zwitterionic double-network hydrogels as electrolyte for zinc-ion hybrid supercapacitor/battery

The hydrogel electrolyte is an important part of safety and development potential in zinc-based energy storage equipment due to its inherent low mechanical strength and voltage decomposition. However, hydrogel electrolytes possess a reduced working life for zinc dendrites growth and a narrow voltage window. In this study, a hydrogel electrolyte prepares by the zwitterionic monomer [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) (MS) and sodium alginate (SA) alleviate these problems. The zwitterionic double-network hydrogel has good mechanical strength, inhibits the growth of zinc dendrites, enhances practicability, greatly increases the voltage window (0–2.4 V), and has self-healing properties to its rich functional groups. The assembled zinc-ion hybrid supercapacitors (ZHSs) have a high-power density of 172.33 W kg^?1 and an energy density of 88.56 Wh·kg^?1 at 0.5 A g^?1. The assembled zinc-ion battery also has good electrochemical performance. Flexible ZHSs and batteries provide power to the timer stably under different bending angles. The zwitterionic double-network hydrogel can be applied to both zinc-based supercapacitors and batteries.     

Microstructure,mechanical and tribological properties of Mo–V–Cu–N coatings prepared by HIPIMS technique

A combination of high wear-resistance and low-friction is crucial for improving the wear performance of self-lubricating coatings, which is generally determined by an excellent lubricating effect and mechanical strength. In this study, the Mo–V–Cu–N coatings were prepared by HIPIMS technique with a spliced target of Mo–V–Cu at various charge voltages. The results revealed that Mo–V–Cu–N coatings presented a solid solution phase of B1–MoVN with (200) preferred orientation, and the preferred orientation was enhanced at high charge voltages. Whereas the Cu atoms formed an amorphous phase in Mo–V–Cu–N coatings due to a low Cu content of 2.3–3.6 at.%. As the charge voltage increased to 750 V, more charged metallic ions were accelerated and bombarded substrate surface efficiently, forming smooth and dense Mo–V–Cu–N coatings with a high hardness of 31.0 GPa. All the coatings presented a low friction coefficient of 0.34–0.39 due to the formation of MoO₂, VO₂ and CuO mixed oxides, and the wear mechanism was dominated by abrasive and tribo-oxidation wear at room temperature.     

Convolutional Neural Network Auto Encoder Channel Estimation Algorithm in MIMO-OFDM System

Higher transmission rate is one of the technological features of prominently used wireless communication namely Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing (MIMO–OFDM). One among an effective solution for channel estimation in wireless communication system, specifically in different environments is Deep Learning (DL) method. This research greatly utilizes channel estimator on the basis of Convolutional Neural Network Auto Encoder (CNNAE) classifier for MIMO-OFDM systems. A CNNAE classifier is one among Deep Learning (DL) algorithm, in which video signal is fed as input by allotting significant learnable weights and biases in various aspects/objects for video signal and capable of differentiating from one another. Improved performances are achieved by using CNNAE based channel estimation, in which extension is done for channel selection as well as achieve enhanced performances numerically, when compared with conventional estimators in quite a lot of scenarios. Considering reduction in number of parameters involved and re-usability of weights, CNNAE based channel estimation is quite suitable and properly fits to the video signal. CNNAE classifier weights updation are done with minimized Signal to Noise Ratio (SNR), Bit Error Rate (BER) and Mean Square Error (MSE).     

[2.2]Paracyclophane-Based TCN-201 Analogs as GluN2A-Selective NMDA Receptor Antagonists

Recent studies have shown the involvement of GluN2A subunit-containing NMDA receptors in various neurological and pathological disorders. In the X-ray crystal structure, TCN-201 ( 1 ) and analogous pyrazine derivatives 2 and 3 adopt a U-shape (hairpin) conformation within the binding site formed by the ligand binding domains of the GluN1 and GluN2A subunits. In order to mimic the resulting π/π-interactions of two aromatic rings in the binding site, a [2.2]paracyclophane system was designed to lock these aromatic rings in a parallel orientation. Acylation of [2.2]paracyclophane ( 5 ) with oxalyl chloride and chloroacetyl chloride and subsequent transformations led to the oxalamide 7 , triazole 10 and benzamides 12 . The GluN2A inhibitory activities of the paracyclophane derivatives were tested with two-electrode voltage clamp electrophysiology using Xenopus laevis oocytes expressing selectively functional NMDA receptors with GluN2A subunit. The o-iodobenzamide 12 b with the highest similarity to TCN-201 showed the highest GuN2A inhibitory activity of this series of compounds. At a concentration of 10 μM, 12 b reached 36 % of the inhibitory activity of TCN-201 ( 1 ). This result indicates that the [2.2]paracyclophane system is well accepted by the TCN-201 binding site.     

Synthesis and characterization of SrFeOx hetero-film resistance-switching device with low operation voltage

As a critical topological phase transition material, SrFeO_x could play an essential role in the field of resistive memory. How to implement resistance-switching more softly and ensure the stability of materials has always been a relevant research hotspot. Regulating the oxygen environment during the deposition process of the films can effectively control the stoichiometry of the functional layer and then improve the resistance-switching characteristics of the device. In this paper, a SrFeO_x hetero-film was prepared by oxygen pretreatment on the SrRuO₃ surface before SrFeO_x deposition, and the as-assembled micrometer-scale device exhibits a low set operating voltage of 0.6 V and favorable cycling characteristics. The SrFeO_x hetero-film reveals a vertical brownmillerite superlattice-like structure with ～20 nm perovskite buffer layer, which benefits the connection and rupture of conductive filament. Additionally, XPS and UV–vis were used to analyze the bonding energy and band gap of SrFeO_x hetero-film, and offers the experimental basis for the explanation of the conductive mechanism. Therefore, the device based on SrFeO_x hetero-film with low operation voltage provides a reference for low power consumption research on topological phase transition material.     

Recycling spent lead acid batteries into aqueous zinc-ion battery material with ultra-flat voltage platforms

The harmless disposal of lead paste in the spent lead-acid batteries (LABs) remains an enormous challenge in traditional pyrometallurgical recycling. Here, we introduced a hydrometallurgical method for the recycling of the spent LABs’ waste to obtain the β-PbO as a novel zinc ion batteries (ZIBs) active material. The obtained β-PbO exhibits ultra-flat charge/discharge voltage platforms (0.21 mV/(mAh g^?1)) and stable specific capacity. During the charge/discharge, the β-PbO spontaneously triggers the formation of (ZnSO₄)[Zn(OH)₂]₃·5H₂O (ZHS) micro-sheets as a surface passivation layer. Moreover, the ex-situ X-ray spectra reveal that the reversible phase transformation occurs between PbSO₄ and Pb with the assistance of ZHS by adjusting the PH value on the electrode-electrolyte interface. The synergistic two-phase-reaction mechanism generates ultra-flat voltage platforms upon the charge/discharge. This “energy-saving and environment-friendly” recycling route eliminates the major source of emission of pollution particulates/gases compared to the traditional pyrometallurgical recycling, while at the same time replacing energy-consuming and environmentally detrimental processes of synthesis of current ZIBs cathodes.     

Design,Synthesis, and in vitro Evaluation of P2X7 Antagonists

The P2X7 receptor is a promising target for the treatment of various diseases due to its significant role in inflammation and immune cell signaling. This work describes the design, synthesis, and in vitro evaluation of a series of novel derivatives bearing diverse scaffolds as potent P2X7 antagonists. Our approach was based on structural modifications of reported (adamantan-1-yl)methylbenzamides able to inhibit the receptor activation. The adamantane moieties and the amide bond were replaced, and the replacements were evaluated by a ligand-based pharmacophore model. The antagonistic potency of the synthesized analogues was assessed by two-electrode voltage clamp experiments, using Xenopus laevis oocytes that express the human P2X7 receptor. SAR studies suggested that the replacement of the adamantane ring by an aryl-cyclohexyl moiety afforded the most potent antagonists against the activation of the P2X7 cation channel, with analogue 2-chloro-N-[1-(3-(nitrooxymethyl)phenyl)cyclohexyl)methyl]benzamide ( 56 ) exhibiting the best potency with an IC₅₀ value of 0.39 μM.     

An iterative approach for the discrete‐time dynamic control of Markov jump linear systems with partial information

The , and mixed dynamic output feedback control of Markov jump linear systems in a partial observation context is studied through an iterative approach. By partial information, we mean that neither the state variable x(k) nor the Markov chain θ(k) are available to the controller. Instead, we assume that the controller relies only on an output y(k) and a measured variable coming from a detector that provides the only information of the Markov chain θ(k). To solve the problem, we resort to an iterative method that starts with a state‐feedback controller and solves at each iteration a linear matrix inequality optimization problem. It is shown that this iterative algorithm yields to a nonincreasing sequence of upper bound costs so that it converges to a minimum value. The effectiveness of the iterative procedure is illustrated by means of two examples in which the conservatism between the upper bounds and actual costs is significantly reduced.     

Analysis of color volume of multi‐chromatic displays using gamut rings

There are claims that multi‐chromatic displays can achieve a wider color gamut by the use of additional highly saturated secondary color channels. However, there are other claims that these displays lose lightness and/or color saturation at brighter levels. These apparently divergent views have led to some controversy in the display industry and at standard setting organizations. This study examines the color gamut volume for a variety of simulated and measured multi‐chromatic (sometimes incorrectly referred to as “multi‐primary”) displays using combinations of white and/or secondary color channels, such as cyan, magenta, and yellow. Furthermore, a two‐dimensional gamut representation, referred to as “gamut rings,” is introduced to illustrate that the addition of nonprimary optical color channels to a trichromatic (RGB) display can result in a significant decrease in the chroma at higher lightness levels. The additional saturated color channels can increase the gamut volume only around their hues at darker levels. The results also confirm the validity of comparing the color light output and white light output for revealing the design trade‐offs between the high‐peak white and the color‐image brightness for multi‐chromatic displays.